Kenwood TK-780 Service Manual Supplement page 23

SB
TX-RX unit (A/2)
Foil side view
ST
TX-RX unit (A/2)
Component side view
RXAO
R529
RXAI
TX-RX unit (B/2)
Foil side view
TXAO
R571
TXAI
4. Ignition Sense Cable (KCT-18 : Option)
The KCT-18 is an optional cable for enabling the ignition
function. The ignition function lets you turn the power to the
transceiver on and off with the car ignition key.
If you use the Horn Alert function or the Manual Relay
function, you can turn the function off while driving with the
ignition key.
4-1. Connecting the KCT-18 to the Transceiver
1. Install the KCT-19 in the transceiver. (See the KCT-19
section.)
2. Insert the KCT-18 lead terminal (
square plug ( ) supplied with the KCT-19, then insert
1
the square plug into the KCT-19 connector (
INSTALLATION
LOK
E
DEO RD2 5C C4
C3
TD2 RD1 OP
SQ
C2
TD1 FW C1
PTT MPTT
) into pin 3 of the
2
).
3
KCT-19
Fig. 3
4-2. Modifying the Transceiver
Modify the transceiver as follows to turn the power or
the Horn Alert or Manual Relay function on and off with the
ignition key.
1. Remove the lower half of the transceiver case.
2. Set jumper resistors (0 ) R151 and R152 of the TX-RX
unit (A/2) as shown in Table 1.
Operation when KCT-18 isconnected
KCT-18 cannot be connected
Power on/off and Horn Alert or
AUX-A on/off
Horn Alert or AUX-A on/off, Timed power off
Power cannot be turned on
Table 1 R151 and R152 setup chart
R152
R151
KCT-19
CN7
Fig. 4
TK-780/H
3
1
Contact
3
13
15 6 2
1
KCT-18
R151 R152
Enable Enable
Disable Enable
Enable Disable
Disable Disable
TX-RX UNIT
(A/2)
ANT
23